Physics
Articles about matter, energy, forces and physical laws.
Pellet
Pendulum
Penetration power
Penetration power (projectiles and barriers)
Period (physics)
Permeability (electromagnetism)
Magnetic permeability (electromagnetism)
Permeance
Permeance: how easily matter or energy passes through a medium
Perpetual motion
Phase
Phase (cyclic states in nature and science)
Phase difference
Phase velocity
Phase velocity is the speed at which a particular phase of a single-frequency component of a wave propagates; distinct from group velocity and affected by dispersion and the medium
Phenomenon
Phenomenon: definition, origins, types, and uses
Philosophiæ Naturalis Principia Mathematica
Phonon
Phosphorescence
Phosphorescence: slow photoluminescence and glow-in-the-dark materials
Photocathode
Photocathode: light-sensitive electron-emitting electrode
Photoelectric effect
Photoelectric effect: emission of electrons induced by light
Photographic filter
Photographic filter: types, uses, history, and practical guidance
Photon
Physical
Physical (term): meanings, uses, and distinctions
Physical coefficient
Physical compression
Physical constant
Physical fitness
Physical fitness: components, measurement, history and practical importance
Physical law
Physical object
Physical object (in physics and everyday use)
Physical property
Physical quantity
Physical system
Physical system (physics)
Physicalism
Physicalism: the philosophical view that reality is fundamentally physical
Physicist
Physicist: Role, Methods, History, and Notable Figures
Physics
Physics: study of matter, energy, space and time
Physics examines matter, energy, forces, space and time. It develops laws and models from classical mechanics to quantum theory and underpins many technologies.
Physique
Physique — human body build, types, and significance
Picometre
Picometre (pm) — SI unit of length equal to 10⁻¹² metre
Picosecond
Piezoelectricity
Piezoelectricity: principles, materials, history, and applications
Pion
Planck constant
Fundamental physical constant linking a photon's energy to frequency; central to quantum mechanics and the modern SI system, often used in the form ħ = h/2π.
Planck length
Planck mass
Planck time
Planck units
Planck's law
Planck's law — spectral distribution of blackbody radiation
Plane wave
Plasma
Plasma (physics)
Plasma (physics): the ionized state of matter and its properties
Plasma lamp
Plasma lamp (plasma globe)
Plasma window
Plasma window: a magnetically confined plasma interface between vacuum and atmosphere